EARTHQUAKES & VOLCANOES REVIEW
Which seismic waves are the fastest?
P waves
Which seismic waves are the first to be recorded?
P waves
Which seismic waves are the second to be recorded?
S waves
Which seismic waves can only travel through solids?
S waves
Which seismic waves are the slowest?
L waves
Which seismic waves travel on the surface?
L waves
What is the boundary between the crust and the mantle due to the change of speed of seismic waves?
Moho
What are the areas called where neither S nor P waves can be detected?
Shadow zones
What is the theory that says energy builds up on each side of a fault and the rocks move slowly and then spring back to their original shape?
Elastic rebound theory
What are small tremors that occur after the first release of energy?
aftershocks
What is the area where the slippage first occurs inside the earth?
focus
What is the point on earth’s surface directly above the focus?
epicenter
What are the three classifications of foci?
Shallow, intermediate, and deep
What are the three major earthquake zones?
1.Pacific Ring of Fire 2.Mid-ocean ridges 3.Eurasian – Mediterranean mt. belt
What is the name of the fault in California where the Pacific plate and North American plate slide past each other?
San Andreas Fault (technically it’s the N. American plate and the Juan de Fuca plate)
What is the device used to record earthquakes?
Seismograph
How many stations are needed to locate an earthquake?
three
Which scale measures the magnitude or the amount of energy released from an earthquake?
Richter Scale
What are the numbers for the Richter scale?
Arabic Numerals They begin a 1-2 and it is an open-ended scale, based on the seismograph’s reading.
Which scale measures the intensity or amount of damage from an earthquake?
Mercalli
What are the numbers for the Mercalli Scale?
Roman numerals
What can be generated from an earthquake with an epicenter on the ocean floor?
Tsunami
What is the molten rock beneath earth’s surface called?
magma
What is molten rock on earth’s surface called?
lava
What is it called when one plate moves under another plate and forms volcanic mountains?
subduction
What is it called when plates move apart and magma rises to form new ocean floor?
Sea-floor spreading
What are areas of volcanic activity within a plate (not on a boundary) called?
Intraplate volcanism (aka hot spot)
What is the lava that comes from quiet eruptions called?
Mafic (aka basaltic lava)
What is the lava that comes from explosive eruptions called?
Felsic Lava (aka rhyolytic lava)
What is mafic (basaltic) lava that looks ropey and wrinkled when it is hardened?
pahoehoe
What is mafic (basaltic) lava that is sharp and jagged when it hardens?
aa
What is the volcanic cone that has gently sloping sides from quiet explosions?
Shield Cone Volcano
What is the volcanic cone that has steep sides from explosive eruptions?
Cinder cone
What is the volcanic cone that is a combination of quiet and explosive layers?
Composite Cone (aka stratocone)
What is a funnel shaped pit at the top of a vent that formed when a volcano exploded?
crater
What is formed when a volcanic cone collapses when emptied, leaving behind a large basin that can fill with water?
caldera
The name of a volcanic fragment is determined by what?
Size of the particle
What is the general name for rock fragments that are ejected from a volcano?
tephra
What are the two smallest types of tephra?
Dust and ash
What are clots of lava that spin into the air and cool to make a spindle shape?
Volcanic Bombs
What is the name of the largest volcano – on Mars?
Olympus Mons
What is the name of Jupiter’s moon that has the most active volcanoes?
Io
This concludes today’s fun. Please put everything away and let’s begin the test!!!